The advantages of rotary wheelchair lifts for private vans is set forth in Braun et al U.S. Pat. No. 4,664,584 which discloses and claims the Braun L800 fully automatic Swing-A-Way.RTM. brand family of wheelchair lifts. The L800 lift is particularly suited for private usage as the same people will be using the lift over and over, so they will be familiar with the fact that the platform remains deployed at all times and may be traversed safely. A portion of the lift mechanism projects into the doorway and the platform is relatively small, having a single telescoping extension and automatic, pivoting front and rear roll stops. It also employs a fold-down handrail which, in the down position, secures the platform telescoping mechanism so that it does not move when stepped-on.
However, in a commercial transit vehicle environment, where the floor is higher off the ground, there is a stairwell entry, and seating is at a premium, such a continuously fully-deployed lift, which would overhang into the stairwell, would not be suitable. Further, it is not feasible to undertake the extensive education of the vast numbers of consumer riders on how to enter properly, including stepping on the platform to enter or exit.
Accordingly, there is a need for a heavy duty rotary lift for transit vehicles which is passive and fully power stowable, is electrically, hydraulically or manually actuable, and takes a minimum of floor space, yet meets the requirements of providing lifts for wheelchair users in public transport.